Field of the Invention
The present invention relates to an electrode assembly for a polymer secondary battery cell, and more particularly, to an electrode assembly for a polymer secondary battery cell, which is a new type of electrode assembly manufactured by only a stacking process without a folding process and in which electrodes are aligned with or close to a separator.
Description of the Related Art
Secondary batteries may be variously classified according to a structure of an electrode assembly. For example, the secondary batteries may be classified into a stacking type structure, a winding type (jelly-roll type) structure and a stacking/folding type structure.
Here, in the stacking type structure, a cathode, a separator and an anode are cut in predetermined sizes and then stacked in turn, thereby defining an electrode assembly. At this time, the separator is disposed between every cathode and anode.
In the winding type structure, the cathode, the separator, the anode and the separator are provided in sheet shapes, stacked in turn and then wound, thereby defining the electrode assembly.
In the stacking/folding type structure, a full cell or a bi-cell is provided and wound through a separator sheet, thereby defining the electrode assembly. The cathode, the separator and the anode are cut in predetermined sizes and then stacked in turn, and thus the full cell or the bi-cell may be provided (the full cell or the bi-cell includes one or more cathodes, separators and anodes).
However, in the stacking type structure, since an electrode unit (the cathode, the separator and the anode) defining the electrode assembly are separately stacked, precise alignment of the electrode assembly is very difficult, and too many processes are required to produce the electrode assembly. And in the stacking/folding type structure, since two lamination apparatuses and one folding apparatus are required, a manufacturing process of the electrode assembly is very complicated. Particularly, in the stacking/folding type structure, since the full cell or the bi-cell is stacked through a folding process, precise alignment of the full cell or the bi-cell is difficult.
Recently, in order to remedy these limitations, a new manufacturing method which may manufacture the electrode assembly by only a stacking process, may precisely align the electrode assembly, and also may improve productivity thereof has been proposed by the applicant (Patent document 1).
Here, referring to FIG. 1, in a typical stacking type electrode assembly, each of a first polar electrode 14 and a second polar electrode 12 has a much smaller size than that of a separator 16, and the separator 16 is moved between the first and second polar electrodes 14 and 12, and regular alignment is impossible, and thus there is a limitation in stability. And thus a separate alignment process has to be additionally performed in order to overcome the limitation.